Quadratic Formula

Question

what is a quadratic function in ​standard form​ that has vertex at (5, 0) and a vertical stretch of -3?

(it’s a homework question I’m stuck on)

Answer 1

start with vertex form

y = -3(x-5)^2

now expand

y= -3(x^2-10x+25)

y= -3x^2 +30x-75